I have a 26 touring and am thinking about switching over to 12 volts. Lang's sells the cutout and bulb kit for 80 bucks. I want to do a good bit of night time driving and plan to add tail lights and signals to the rear end. My question to you guys is regarding the generator. Would I be better off going with the gear driven alternator or sticking with my stock generator? She's not a show car.

David, My personal preference would be to go with a gear driven alternator since they make them to bolt right up to where a generator would go. I don't have anything against generators but since you are going to night drive, I would want the best possible option. A good battery I would also consider.

I have long believed/understood that a 6 volt 50 candlepower bulb will be just as bright as a 12 volt 50 candlepower bulb. Yes? No? Bulbs of equal candle power or wattage should produce the same amount of light independent of their rated voltage, right?

A 50cp bulb is a 50cp bulb. Most of the problem with 6 volt headlights is connections and reflectors. If those are fixed the light is fine. If you want 1 million candlepower headlights that is another issue. There are other facets of the conversion to consider. This is one of those topics that turns out like religion, politics, oil or coils. Everyone has an opinion.

6 volts is fine for me. I dont drive at night so for me that would be the only reason to use 12 volts. And I am not to sure it would be that much brighter anyway. Slow night driving will get you killed in some areas and most folks dont drive slow at night in "modern" cars these days.

Investing in proper lighting and a fully operational original system might be the way to go. The 6 will do all that the 12 does and the $80 is better invested in safety (lighting) than "upgrading" to 12 vts. My 2 cents.

My '26 coupe was once converted to 12v, but I changed it back to 6v after seeing what the extra torque did to the bendix spring. When I saw that and the damage to the flywheel ring gear from the slamming of the bendix into it, it scared and worried me that such damage could have occurred and what other damage (particularly to the mag coil and spark coils), might it have done, so, during my recent engine overhaul and re-wiring, I changed it back to 6v and I am very pleased with it.

If you are pleased with your 12v system, that is great, but In my humble opinion, there is no reason to change to 12v because a properly adjusted Model T should run perfectly on the 6v system it was designed to use. If it doesn't there is an underlying problem that should be addressed that will still be there after the conversion to 12v is made.

Here are afew pictures. Compare the last three showing the damaged bendix spring, with the first picture showing the undamaged spring I replaced it with. Jim Patrick

PS. Notice on the undamaged spring, how the bolt holes are even with eachother and how on the damaged one the bolt holes are on opposite sides. That took alot of slamming torque to over twist the spring like that! Jim

So, what if I stay with my 6 volt system and add a second battery, a 12 volt, just to run LED tail lights/signals? The 12 volt battery could be on a trickle- charger whenever the car is not in use. Heck, that same battery could power my coils too, right? Has anyone done this?

You could add a second 6 volt batterie, and a switch so you could charge either batterie, and then you would have 12 volts for the lights and 6 volts for everything else. We had a John Deere that had two 12 volt batteries, part of the tractor was 12 volt and part was 24 volt, the batteries were charged by a 24 volt alternator, but only one batterie was used for the electrical system, as I recall, it was a royal pain in the ass to maintain, but you could also go the same route with two 6 volt batteries and a 12 volt alternator. Best Gus

I like local guys that change to 12 Volts because I sell bendix parts to guys that damage their bendix. I even get to sell some heavier Model A bendix parts to guys that tear up their lighter T bendix, that other wise I could not sell.

Dave, is that an original foot starter button? I purchased an original on ebay that looks just like that, and even after 84 years, it is much more reliable and efficient than the unreliable reproduction I replaced it with. Jim Patrick

David, the biggest concern with night driving is saftey. If you drive like I do you'll be running 35 to 40, with 6V you are not going to out drive your head lights. The danger is the other cars coming up behind at 55 to 70. I don't drive much at night but when I have to, I place a magnetic led flashing light on the back, It's very bright and can be seen a long way back. Have fun, be safe, KB

2: Some people, very few, will know it is as it came from the factory.

3: The six volt light bulbs and batteries are hard to find and expensive so you will not get hit by a truck while driving your Model T and having fun on the road because you will be out looking for parts in your modern car which is safer than a Model T.

4: You will not be distracted by Cell phones, digital camera, GPS, and other electronic toys because you can't charge them on six volts in the car and you will keep your eyes on the road.

5: You will not spill hot coffee on yourself or burn yourself with a hair dryer because you will not be bothered by the inverter that converts 12 volts to 120 VAC house current which lets you use house hold items in your car.

6: you will only break a Bendix spring once every 20 years rather than once in every 51 years as I have done using 12 volts in my T's

7: You will have the inefficient battery regulator that simply turns on and off and sticks in the closed position often rather than the sophisticated three way type that regulates voltage and amperage by constantly checking battery voltage and controlling the charging rate to both protect the battery and the generator.

8: Your six volt battery will assist in faster cold starts than the magneto can provide and you will be required to have your magneto in good working order in order for your engine to run efficiently on the factory coils at a voltage higher than six volts.

9: You will enjoy a stock engine because the six volt systems usually fail when attempting to crank hot start high compression engines thus keeping you safely in the garage or on your trailer.

10: If your Model T is a Speedster and you are using a six volt alternator, you will be safer at home after being asked not to attend some Speedster events due to parts made after 1927. Any belt driven generating system, generator or alternator, is cause for disqualification.

David - I just did the dual 6V battery trick with my '15 to convert to LED lighting. The fact is - the better, brighter LED replacement lamps are being developed only for modern 12V cars. Since my '15 is a non-starter car, that meant a pair of small inexpensive gel-cells. The two batteries are wired in series, with the jumper between the two (6V) connected to the battery post on the coil box. The 12V tap goes to the LED lights and the mag charger circuit.

For your car, a pair of 6V Optimas ($$$) would fit in the existing battery box. You would wire them in series and send the 6V center tap to the starter. 12V would go to the lights, other accessories, and the generator. Nice thing about a generator is that it doesn't care what voltage it's charging. Both batteries would stay charged, and your Bendix, lights, and accessories would all be happy. Also, if you went with a voltage regulator instead of a cutout, you could just wire it up and forget about it. Best of both worlds.

Now true, the batteries are running a bit out of balance this way. Maybe John Regan has some thoughts on this, since he makes both the mag chargers and the voltage regulators.

Frank I drive my car a lot and have not encountered these advantages as you call them! My 24 is stock except for the fun projects voltage regulator. Matter of fact I tell people the T is the only truly dependable car I own. Have fun, KB

Yes, 6V LEDs are available, but what you get for what you pay makes the 12V secondary electrical system well worth the effort (my 2Ę). Like I said, the development of automotive LEDs is going where the money is - the 12V market. The tail light I used is this one. It has very bright stop, tail, and license plate lights all rolled into one bulb...for $12.95. The same company also sells 12V LED turn signal flashers for $12.95. Priced a 6V turn signal kit lately?

I tried to keep everything 6V, but finally gave up and went with the dual system. I like driving my antique cars day or night, so better lighting is something I'll always concede to. Oh, and my Model A Tudor got an eye-level LED stoplight bar. It sits on the rear window sill, barely visible until it comes on. Same trick - the red LED light bar ($7.95 at Harbor Freight) gets 12V, the rest of the car gets 6. I haven't converted the headlights yet. That gets a bit more challenging with high beam/low beam.

I think I was not too clear to some of you. I do not advocate changing to 12 volts. My six volt interstate batteries start my Ts just fine. I always change to 20 weight oil in the fall but got lazy and didn't do it on my CD this winter. I have been driving it all winter and it starts just fine in an unheated garage.

As for driving at night I try to avoid it when possible, but I know you sometime do get cought out after dark. Robert Ducharme and I got cought out in the dark at Estes Park a month or so ago. We had been on a 300 mile day tirp and didn.t mnake it back in time. We drove down the Canyon from Estes Park to Loveland in pitch black dark. I kept watching the right hand white line so I could tell I was still on the road. We kept getting cars stacked up behind us and their headlights on the verticle windshield was blinding me so I pulled my rear window curtain. It would not stay down, so I stopped and put a pair of vise grips on it.

NOW: As to being hit at night from behind. I don't use an original tail light on any of my electric cars. I go to Napa and get a modern slightly larger tail light which is much brighter becase you can put in a larger light bulb with more CP. I also use a magnetic rear LED light which you can see in the picture below. The best light I use on the back though is a LED bicycle light. You can see that puppy for miles. In the picture below you can't see the bike light because it so small.

I think you can see the yellow light just under the window on the picture above. It is magnetic and I can change it to one of my other cars when I want. You can change it to a blinking light (that what I usually do) or you can change it to a steady light. If you look real close you can see the bike light on the license plate between the tail light and the stop light. Like I said above its the brightest light of all. I made a spring clip for the bike light so I can also change it from one car to another.

Both the big yellow light and the bike light are battery operated so they are easy to change. It seems like the batteries last for ever. I have gone out to the garage and found that I forgot to turn them off and they are both working (blinking} the day after I was drving the Ts. The large yellow light came from a Truck supply shop and two of them were given to me from a friend. The bike light came from a bike shop.

So there you are making 30 mph and someone talking on their cell phone or texting might not be paying attention ?? Do you need to drive a T at night?? Bud.Ps,I use 12 volt for starting when im lazy and i can say 12 volt will Never Harm the bendix!! Bud.

While we are on the subject of 6v vs.12v, I have a question that has been bothering me.

We are told never run the generator without a battery load on it or the voltage will increase tremendously, burning out the generator. OK, that seems perfectly logical.

Even though my cutout on my TT functions perfectly I did add the Fun Projects electronic regulator so as to not overcharge the battery.

Now, if the lights are off and the battery is fully charged the current load on the generator is extremely low or even nonexistent. Whatever the output of the generator is the regulator allows only around 7.2 volts to leave the regulator.

My big question is how this apparently series voltage limiter has any effect on the voltage generated within the generator. If the gen. is developing, say, 30 volts under a no load condition but the regulator is passing only 7.2 volts, why doesn't the gen. look at this as being essentially disconnected from the load and run away, voltage wise?

Does the electronic regulator have an internal shunt resistor that presents enough of a load on the gen. to prevent it from running away?

It is nearly impossible to explain the total operation of the VR in layman's terms. I mean no disrespect to anyone by saying that. It is just that most folks think there are only 2 types of regulators - namely series type or shunt type. The T regulator is neither. The reason that a T generator burns out in the absence of a load on it is that the field winding is essentially being powered by the output of the generator via the 3rd brush acting as a TAP on the output. While the 3rd brush does NOT get full output to the field - it gets a portion of it such that if the output goes up - the field current goes up. They act together in the same direction. Further increase of field current gives more output which gives more field current which gives even more output which gives even more field current......and the process continues until something starts burning. The Fun Projects VR controls the field current so when the output of the VR is high it reduces the field current to lower it. Conversely when the output is low it increases it thus it works opposite of the 3rd brush acting alone. The VR is NOT acting separately from the generator as when you have a series regulator or shunt regulator that is on the output of the generator with the generator putting out some fixed power and the regulator then acting to dissipate it with either a series loss or parallel load loss. The VR controls the generator. The VR will NOT work by itself to do anything. It only knows how to control the generator and that is why the instructions for the VR make it very very clear that the generator MUST be a known good generator. If not then the VR will be toasted along with the Generator. The good news is that the VR protects the generator even if the battery is disconnected by some means (loose cable - loose ammeter wiring...etc). The VR will instantly shut down the generator via a separate circuit designed to look for a sudden and unusually high rise in voltage. The VR will "crowbar" the generator output and disconnect the battery output electrically and wait for sanity to return. If sanity returns then the special circuit will self reset and all is well. If the generator will NOT respond and shut down then the VR will go into FAIL SAFE mode and die on purpose by permanently shorting the generator post to ground with a hard short. It will open up the battery side and eventually you should notice your generator is not charging. The VR thus will give up its life to save the generator windings. The VR can be repaired by us if in that mode and repairs are not very expensive and there is a flat rate to fix it if not tampered with. If you open up the VR yourself then that flat rate is no longer available. We will still fix the VR for you if repairable but not for the low flat rate. There are NO user serviceable parts inside. A few have opened the thing up and will attest to the truth of this statement. The VR will not go into fail safe mode by itself so if we find it in this mode - we coach you to find out what happened since if you simply put the VR back on the same generator and make no attempt to find the problem - the VR will simply repeat the same dance over again.

So long as the VR case is tightly mounted on the generator and the generator post is tightly connected to the input terminal of the VR - the generator should be protected from burn out. It has not failed yet in a single case to have not protected the generator when something has gone awry which usually is during the first install when things are a bit shakey. A KNOWN GOOD GENERATOR is the key to your success with our VR and then the ability to read and follow instructions to the letter. I am happy to answer any technical questions here or when you call. I would prefer to answer your questions before you see some smoke.

I have a late night wedding my 1919 touring car has to attend in the early spring so I have bought a 12 volt starter and alternator from Mr. LD Becker. Mr. Becker makes the starters from early model GM starters and converts them to work on the model Tís. Iím told that the 12 volt starter will not slam the ring gear like the 6 volt would on 12. I will be using 12 volt Halogen bulbs for brighter lights for safer night time driving. I rarely ever drive at night but as this wedding is family and I was asked personally for the T. After the wedding Iíll put everything back to the 6 volt system.

The automotive industry is considering changing to a higher voltage and perhaps as high as 24 volts. The thinking is they will use less wire connecting things together and save money and weight. Why else would most aircraft use 400 volts on a lot of equipment today ? They will continue to make 12 volt batteries for a while but six is to soon be nixed. Golf carts be damned, they will have to walk like the rest of us do in these times of change for the sake of change.

Keith, go into your local drug store at 10:00 o'clock at night and try to get a six volt bulb or battery. Or try to get a jump start, or borrow a charger out in the real world when you are in trouble and the children just want to go home . . . now !

When you go to get a six volt battery the big box stores do not have them. The battery stores have three or four and about 50 or more different sizes of 12 volt selections. Again, the automotive industry is considering changing to a higher voltage and perhaps as high as 24 volts. The thinking is they will use less wire connecting things together and save money and weight. Why else would most aircraft use 400 volts on a lot of equipment today ?

Keith, again, please go into your local drug store at 10:00 o'clock at night and try to get a six volt bulb or battery. Or try to get a jump start, or borrow a charger out in the real world when you are in trouble and the children just want to go home . . . now !

When you go to get a six volt battery the big box stores do not have them. The battery stores have three or four and about 50 or more different sizes of 12 volt selections.

Some things just have to move along.

Try an alternator on your Speedster at some events and go home without playing the game.

If you have never had these nice times as you say you never have had, then you are truly blessed. Some things just have to move along with what is available in these times of "change".

If you have never had these "nice" times, then you are truly blessed and my you continue to be so anointed ! Frank

The starter bendix spring looks just like Jim Patrick's pictures on 6V. They get that way over decades of use. My '15 has been on 12 volts since the Johnson administration. No problem, don't worry about it.

Yes indeed, but that would be taking away the fun of the 'I Know Best' gang who seem to have nothing better to do than clog up a useful forum with guesses and hearsay - why? To make themselves look experts? To pass the time? I am grateful for all the useful information on this forum, but I am getting fed up with the rubbish in between from ill thought out respronses from self appointed experts. Like I said in another thread recently, 'If you don't know, keep quiet'. Thanks, Chris M.

Chris, I don't know most of the answers and I am certainly no expert, but I have owned a Model T for 40 years and, while I may not have the difinitive answer, I, like most of the members here, have many years of experiences that may help others.

I don't think there is one person that comes on here to showoff or try to make themselves look like experts, but there are those that I consider experts and I value their advice, immensly.

Anyone who takes time away from what they are doing to try and help a fellow Member is doing so because thay really feel that what they have to contribute will help. In my book, the more opinions and experiences that are expressed the more choices of solutions the questioner has to choose from. It is criticisms and ridicule of those trying to help that we don't need.

If everyone who didn't know, kept quiet, it would be a very dull and quiet Forum, indeed. Jim Patrick

Most modern jet aircraft use 28 volts DC to start the auxiliary power unit (APU). After that happens most items are operated on AC volts, typically 115 V / 400 hz.

There are many ways to skin a cat, as the saying goes, and so there are some aircraft that use so - called "wild frequency" AC power because it is efficient and weight saving. This is a constant voltage, variable frequency AC power.

It is relatively easy to regulate voltage output from an AC generator. Not so frequency; typically the easiest way to regulate frequency is through the use of a constant speed drive (CSD) in between the generator and the engine. These are heavy, complicated, and troublesome; so the industry has generally moved away from the CSD for new designs.

I run a 12v deep cycle battery with 1157 bulbs with one peg ground off for headlights. I pulled the bunners out of the oil lamps and slide in older metal 1157 sockets and tried to hide the wires. This works ok when all the lights are lit for show but I really try to stay away from night driving, noone can see the car at night anyway. The engine startes and runs just fine on 12v and a voltage test with a meter indicates when a recharge is needed. Again this works for me as I really don't want to spend much time wrenching when the weather is nice and I could be driving.

I changed to a 12v system back in the 70's since I could not find reliable 6 volt batteries. Like many posting here I have broken my share of bendix springs until I started using a Model A bendix spring and grade 8 bolts to hold them on. I think I have only destroyed two bendix drives on two T's over the past 40 years. I used the old original generator for many years but now have a modern 12v generator that one of our vendors sells. The generator doesn't look so out of place to the general public. - John

Connecting 12V to an unmodified 6V starter motor can never be acceptable. I've driven on freeways and out in the the middle of nowhere at night and find the standard 6v headlights just fine for the speed at which one should be driving. Too many people want their T to be a de facto modern car perhaps?

It's a simple matter of the 12 volt batteries being $29 and available anywhere versus twice that for a 6 volt and good luck finding one in the middle of no where while on tour. I have 6 volt headlight bulbs in series replacing the original 9 Volt bulbs in my '15, but do use 12 volt tail and stop lamps. None of my T's have any sort of charging system. I just hook up the smart charger when the car is not in use.

My starter gets used only once in a blue moon. One or two pulls on the crank starts the car. The starter is handy if you stall in the middle of an intersection though!

The secret to a good electrical system is good wiring, and a good starter switch, and of course a good battery with clean terminals. Both my '25 pickups start really good, and fast too with 6 volts. I also use the old 1158 21-2 cp bulbs in the headlights, and they are fine. Those 50 cp bulbs just drain the battery, but they sure are bright. I don't know if 1158's are still available or not, but I pick them up at swap meets.

Then, there are those of us who use 6v dry cells to power the coils for starting, our right hand for cranking (Hee hee hee), our magneto for normal running, headlights and horn, and lamp oil for cowl and tail lights. I must be a glutton for punishment.

Royce - And the other problem is that IF you are lucky enough to find that 6 volt battery in the middle of nowhere on a tour, it's probably in bad shape from having been sitting on a shelf in some back storage room in the store for about a year and a half without ever having been charged up!

If you do switch to 12v, I did it on my 14 touring, I would recommend an alternator and rewiring the starter for 12 volt operation, basically the coils are wired in series rather than parallel. There has been articles on this modification on this forum. Also I would recommend only using the starter button to energize a starter relay. It can be mounted along side the button and will give years of reliable service. By the way Ivan, I recognize the road with the speedster, but there is no shadow under the car!!!! Are we sure itís San Diego???

[Connecting 12 volt to a unmodified 6 volt starter motor can never be acceptable] By John H. Pure Bunk!!! Go to a tractor site and see how many tractors have been converted to 12 volt without touching the starter!!! Im far from being a expert but i think most starters will handle up to 24 volt in short cranking times?? Bud.

I think it depends on the starter. There is a lot of evidence to suggest the T starter holds up pretty well. I have to wonder how much bendix spring damage is caused by forgetting to retard the spark and how much is caused by 12 volts.

Having said that, we have a Farmall H that someone had converted to 12 volt before we got it. It eventually cracked the bearing housing on the rear of the starter. That rear plate appeared to be pot metal. I went to a tractor junk yard and bought another rear plate off of a junk starter. It was cast iron. I figured it would last longer. WRONG! It didn't last more than a month or two. We resorted to cranking it with the hand crank for a couple of years until we had it painted and had a few other things done. At that point, I wanted to go back to 6 volt, but it's hers and she let the guy talk her into staying with 12 volts, but had some work done on the starter to make it stand up to the 12 volts. Not sure what they did, maybe wired in a shunt or something? At any rate, it's been fine since then, but before the starter work was done, it committed suicide twice.